Two spherical stars A and B have densities `rho_(A)` and `rho_(B)` , respectively . A and B have the same radius , and their masses `M_(A)` and `M_(B)` are related by `M_(B) = 2 M_(A)` . Due to an interaction process , star A loses some of its mass , so that its radius is halved , while its spherical shape is retained , and its density remains `rho_(A)` . The entire mass lost by A is deposited as a thick spherical shell on B with the density of the shell being `rho_(A)` . if `upsilon_(A)` and `upsilon_(B)` are the escape velocities from A and B after the interaction process , the ratio `(upsilon_(B))/(upsilon_(A)) = sqrt((10 n)/(15^(1//3))` . the value of n is ______.